Plenikowski was born in Zoppot,[1] then a German town on the country's "North Sea" coast. He served in the German Army in World War I and became a member of the Soldier's and Workers' council of Breslau in 1918. After the war he worked as a teacher in Zoppot.[2] He was a member of the municipal parliament of Liessau (1925–28) and the district parliament of Landkreis Großer Werder (1926–1930). In 1926 he joined the Social Democratic Party of the Free City of Danzig and the Communist Party in 1927. He represented the Communist Party in the Volkstag parliament in 1928-1937, at times as leader of the Communist group in it. He was dismissed from public service in 1933.[3] After the ban on the Communist Party on 28 May 1934 by the Nazi Government, it continued to run in the 1935 Volkstag elections as "List Plenikowski".[4]
In 1937 he emigrated to Sweden. In 1940-1941 he was detained at the Smedsbo prison camp. After his release, he settled down in Uppsala. From 1943 onwards he was involved in the Stockholm branch of the KPD.[3] Plenikowski returned to Germany in 1946. He joined the Socialist Unity Party of Germany (SED) and worked in various positions in the SED administration. Plenikowski was a member of the Volkskammer in 1950-1967, candidate to the Central Committee of the SED (1954–1967) and head of the office of the council of ministers (1956–1963).[1]
